Patents Assigned to MTD Southwest, Inc.
  • Patent number: 6945215
    Abstract: A portable, operator-carried power tool having an implement supported on frame, and a lightweight, four-stroke, engine drivably connected to the implement. The engine has a crankshaft situated in a crankshaft housing and a cylinder block secured to the housing, the crankshaft being provided with a crankcase ventilation passage extending between the crankcase and an outlet end in communication with an air/fuel induction passage. A passage establishes communication between the interior of the crankcase and the valve chamber through a cam and cam gear region of the cylinder block. An oil mist generator is connected drivably to the crankshaft for agitating liquid oil in the crankcase to establish a lubricating oil mist. The crankcase, cam region and valve chamber form a containment whereby oil mist is distributed throughout the engine during operation regardless of angular orientation.
    Type: Grant
    Filed: May 22, 2003
    Date of Patent: September 20, 2005
    Assignee: MTD Southwest, Inc.
    Inventors: Shiro Kawamoto, Harry Gene Rickard, John Sheldon, Yoichi Imgawa
  • Patent number: 6863043
    Abstract: A power tool having a rotary implement driven by a four-cycle engine. The engine crankcase is through a passageway which extends through a camshaft to a valve chamber. The rotating shaft member inhibits the escape of lubricating oil when the engine is running while permitting a lubricating oil mist to circulate through the engine.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: March 8, 2005
    Assignee: MTD Southwest, Inc.
    Inventors: Katsumi Kurihara, Shiro Kawamoto, James M. Grayson
  • Publication number: 20040177825
    Abstract: A power tool having a rotary implement driven by a four-cycle engine. The engine crankcase is through a passageway which extends through a camshaft to a valve chamber. The rotating shaft member inhibits the escape of lubricating oil when the engine is running while permitting a lubricating oil mist to circulate through the engine.
    Type: Application
    Filed: December 22, 2003
    Publication date: September 16, 2004
    Applicant: MTD Southwest, Inc.
    Inventors: Katsumi Kurihara, Shiro Kawamoto, James M. Grayson
  • Patent number: 6772726
    Abstract: An oil mist generator is connected drivably to the crankshaft for agitating liquid oil in the crankcase to establish a lubricating oil mist. The crankcase, the cam region and the valve chamber form a closed oil mist containment whereby lubricating oil mist is distributed throughout the engine during operation regardless of angular orientation of the engine. The crankshaft ventilation passage establishes lean crankcase gas distribution to the engine air/fuel intake. The crankcase is designed to avoid flow of liquid oil through the crankshaft passage when the engine is not running.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: August 10, 2004
    Assignee: MTD Southwest, Inc.
    Inventors: Shiro Kawamoto, Harry Gene Richard, John Sheldon, Yoichi Imgawa
  • Patent number: 6666184
    Abstract: A power tool having a rotary implement driven by a four-cycle engine. The engine crankcase is through a passageway which extends through a camshaft to a valve chamber. The rotating shaft member inhibits the escape of lubricating oil when the engine is running while permitting a lubricating oil mist to circulate through the engine.
    Type: Grant
    Filed: February 19, 2002
    Date of Patent: December 23, 2003
    Assignee: MTD Southwest, Inc.
    Inventors: Katsumi Kurihara, Shiro Kawamoto, James M. Grayson
  • Publication number: 20030213458
    Abstract: A portable, operator-carried power tool having an implement supported on an operator-carried frame, and a lightweight, four-stroke, internal combustion engine drivably connected to the implement and supported by the frame. The engine has a crankshaft situated in a crankshaft housing and a cylinder block secured to the crankshaft housing, the crankshaft being provided with a crankcase ventilation passage extending between the crankcase and an outlet end in communication with an air/fuel induction passage. A passage establishes communication between the interior of the crankcase and the valve chamber through a cam and cam gear region of the cylinder block. An oil mist generator is connected drivably to the crankshaft for agitating liquid oil in the crankcase to establish a lubricating oil mist. The crankcase, the cam region and the valve chamber form a closed oil mist containment whereby lubricating oil mist is distributed throughout the engine during operation regardless of angular orientation of the engine.
    Type: Application
    Filed: May 22, 2003
    Publication date: November 20, 2003
    Applicant: MTD Southwest Inc.
    Inventors: Shiro Kawamoto, Harry Gene Rickard, John Sheldon, Yoichi Imgawa
  • Patent number: 6622688
    Abstract: An engine powered hand-held power tool and engine lubrication method is provided, the power tool being intended to be carried by an operator during use. The power tool has a frame, including a handle to be grasped by the operator, an implement affixed to the frame having a rotary input member, and a small four-cycle, lightweight, internal combustion engine attached to the frame for driving the implement. The four-cycle engine has a lightweight aluminum alloy engine block having a cylindrical bore and an enclosed oil reservoir formed therein. A crankshaft is rotatably mounted in the engine block for rotation about a crankshaft axis. A piston reciprocates within the bore and is connected to the crankshaft by a connecting rod. An oil splasher driven by the crankshaft intermittently engages the oil within the enclosed oil reservoir to splash-lubricate the engine.
    Type: Grant
    Filed: February 15, 2001
    Date of Patent: September 23, 2003
    Assignee: MTD Southwest, Inc.
    Inventors: Robert G. Everts, Katsumi Kurihara
  • Patent number: 6568364
    Abstract: An oil mist generator is connected drivably to the crankshaft for agitating liquid oil in the crankcase to establish a lubricating oil mist. The crankcase, the cam region and the valve chamber form a closed oil mist containment whereby lubricating oil mist is distributed throughout the engine during operation regardless of angular orientation of the engine. The crankshaft ventilation passage establishes lean crankcase gas distribution to the engine air/fuel intake. The crankcase is designed to avoid flow of liquid oil through the crankshaft passage when the engine is not running.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: May 27, 2003
    Assignee: MTD Southwest, Inc.
    Inventors: Shiro Kawamoto, Harry Gene Richard, John Sheldon, Yoichi Imgawa
  • Publication number: 20030010311
    Abstract: A power tool having a rotary implement driven by a four-cycle engine. The engine crankcase is through a passageway which extends through a camshaft to a valve chamber. The rotating shaft member inhibits the escape of lubricating oil when the engine is running while permitting a lubricating oil mist to circulate through the engine.
    Type: Application
    Filed: February 19, 2002
    Publication date: January 16, 2003
    Applicant: MTD Southwest Inc.
    Inventors: Katsumi Kurihara, Shiro Kawamoto, James M. Grayson
  • Publication number: 20020148426
    Abstract: A compression relief mechanism for a small four-cycle engine to facilitate cranking. The engine has a single cam actuating both the intake and exhaust valves. The cam has a primary cam surface and a boss extending from its side. The exhaust valve cam follower engages only the primary cam surface. The intake valve cam follower has a first cam follower surface engaging only the primary cam surface and a secondary cam engagement surface engaging only the boss to open the intake valve during a predetermined portion of the engine's compression cycle. The opening of the intake valve during the compression cycle provides compression relief facilitating cranking. The secondary cam follower surface may be provided on either the intake or exhaust cam follower to open either the intake or exhaust valve during the compression cycle to provide the desired compression relief during cranking.
    Type: Application
    Filed: June 11, 2002
    Publication date: October 17, 2002
    Applicant: MTD Southwest Inc.
    Inventor: Michael Billetdeaux
  • Publication number: 20020121262
    Abstract: A portable, operator-carried power tool having an implement supported on an operator-carried frame, and a lightweight, four-stroke, internal combustion engine drivably connected to the implement and supported by the frame. The engine has a crankshaft situated in a crankshaft housing and a cylinder block secured to the crankshaft housing, the crankshaft being provided with a crankcase ventilation passage extending between the crankcase and an outlet end in communication with an air/fuel induction passage. A passage establishes communication between the interior of the crankcase and the valve chamber through a cam and cam gear region of the cylinder block. An oil mist generator is connected drivably to the crankshaft for agitating liquid oil in the crankcase to establish a lubricating oil mist. The crankcase, the cam region and the valve chamber form a closed oil mist containment whereby lubricating oil mist is distributed throughout the engine during operation regardless of angular orientation of the engine.
    Type: Application
    Filed: February 5, 2002
    Publication date: September 5, 2002
    Applicant: MTD Southwest Inc.
    Inventors: Shiro Kawamoto, Harry Gene Richard, John Sheldon, Yoichi Imgawa
  • Patent number: 6374796
    Abstract: A portable, operator-carried power tool having an implement supported on an operator-carried frame, and a lightweight, four-stroke, internal combustion engine drivably connected to the implement and supported by the frame. The engine has a crankshaft situated in a crankshaft housing and a cylinder block secured to the crankshaft housing, the crankshaft being provided with a crankcase ventilation passage extending between the crankcase and an outlet end in communication with an air/fuel induction passage. A passage establishes communication between the interior of the crankcase and the valve chamber through a cam and cam gear region of the cylinder block. An oil mist generator is connected drivably to the crankshaft for agitating liquid oil in the crankcase to establish a lubricating oil mist. The crankcase, the cam region and the valve chamber form a closed oil mist containment whereby lubricating oil mist is distributed throughout the engine during operation regardless of angular orientation of the engine.
    Type: Grant
    Filed: January 19, 2000
    Date of Patent: April 23, 2002
    Assignee: MTD Southwest Inc.
    Inventors: Shiro Kawamoto, Harry Gene Richard, John Sheldon, Yoichi Imgawa
  • Patent number: 6363904
    Abstract: A power tool having a rotary implement driven by a four-cycle engine. The engine crankcase is through a passageway which extends through a camshaft to a valve chamber. The rotating shaft member inhibits the escape of lubricating oil when the engine is running while permitting a lubricating oil mist to circulate through the engine.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: April 2, 2002
    Assignee: MTD Southwest Inc.
    Inventors: Katsumi Kurihara, Shiro Kawamoto, James M. Grayson
  • Patent number: 6345489
    Abstract: A compact, lightweight and easy-to-use wheeled lawn care unit comprising a two-wheeled carriage, a power source, plurality of tools which may be alternatively connected to the power source, a handle and a boom connecting the selected tool to the power source. The power source is pivotally connected to the carriage at a location within its footprint. The unit has a low center of gravity by placing the power source pivot and center of gravity within a cylinder defined by the wheels. The boom extends horizontally from the power source and is of a split boom configuration which allows selective rotation for the boom portions relative to one another. An edger can be selected for the unit, which includes a spring-loaded wheel. The edger may be rotated from a non-working position where the edger blade does not contact the ground to a working position by rocking a handle behind the carriage forward against the bias of the spring. A second more compact version has the shield positioned on the boom.
    Type: Grant
    Filed: February 23, 2000
    Date of Patent: February 12, 2002
    Assignee: MTD Southwest, Inc.
    Inventors: Robert G. Everts, Jeffrey M. Dils, Kenneth M. Brazell, Raul F. Vidal
  • Patent number: 6305909
    Abstract: A Compact blower is provided having a housing defining an engine compartment, cooling air compartment and a volute chamber all coaxially aligned along a vertical axis. An internal combustion engine is oriented within the engine compartment with a vertically aligned output shaft and a forwardly facing fin cylinder. The rotary impeller is affixed to the engine output shaft provided with a plurality of cooling air pump blades projecting upward from a circular disc and oriented within the cooling air pump compartment. The impeller is further provided with a plurality of blower fan blades which project outwardly into the volute chamber. The rotation of the impeller causes air to be drawn into the volute chamber and discharged through the blower air discharge port. Cooling air is drawn through the cooling air pump compartment and directed across the engine and cylinder and ultimately discharged through an upper front portion of the engine compartment in a direction away from the operator.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: October 23, 2001
    Assignee: MTD Southwest Inc.
    Inventors: Mark Jankowski, Clyde J. Smith
  • Publication number: 20010027768
    Abstract: An engine powered hand-held power tool and engine lubrication method is provided, the power tool being intended to be carried by an operator during use. The power tool has a frame, including a handle to be grasped by the operator, an implement affixed to the frame having a rotary input member, and a small four-cycle, lightweight, internal combustion engine attached to the frame for driving the implement. The four-cycle engine has a lightweight aluminum alloy engine block having a cylindrical bore and an enclosed oil reservoir formed therein. A crankshaft is rotatably mounted in the engine block for rotation about a crankshaft axis. A piston reciprocates within the bore and is connected to the crankshaft by a connecting rod. An oil splasher driven by the crankshaft intermittently engages the oil within the enclosed oil reservoir to splash-lubricate the engine.
    Type: Application
    Filed: February 15, 2001
    Publication date: October 11, 2001
    Applicant: MTD Southwest Inc.
    Inventors: Robert G. Everts, Katsumi Kurihara
  • Patent number: 6227160
    Abstract: An engine powered hand-held power tool and engine lubrication method is provided, the power tool being intended to be carried by an operator during use. The power tool has a frame, including a handle to be grasped by the operator, an implement affixed to the frame having a rotary input member, and a small four-cycle, lightweight, internal combustion engine attached to the frame for driving the implement. The four-cycle engine has a lightweight aluminum alloy engine block having a cylindrical bore and an enclosed oil reservoir formed therein. A crankshaft is rotatably mounted in the engine block for rotation about a crankshaft axis. A piston reciprocates within the bore and is connected to the crankshaft by a connecting rod. An oil splasher driven by the crankshaft intermittently engages the oil within the enclosed oil reservoir to splash-lubricate the engine.
    Type: Grant
    Filed: July 2, 1999
    Date of Patent: May 8, 2001
    Assignee: MTD Southwest, Inc.
    Inventors: Katsumi Kurihara, Robert G. Everts